How many mods have you done to your Whizzer?

Actually I bought all of them from Whizzer as they removed them for the first NE5s

Very few were ever sold on the bikes, because Whizzer USA pulled them when they realized the restictor could be removed in a few seconds. Removing the restrictor allowed them to easily exceed 45 MPH and Whizzer felt it important to keep the bikes below 30 MPH to meet some states motorbike [moped] rules.


Do I still have some of the original carburetors? Most likely I do, as I have them on almost all the new edition Whizzers in my collection, including the "Wheelie" machine, and the 2005 record of 68 MPH on my 99.


It think it important to suggest you bring the power level of your motor up before you attempt to use the 26 MM carburetor. The reason is basic as the heads used on the very first NE motors were different [Yes I do have several in stock] and adapted well to the larger carburetor, however the later heads have a much more scrambled flow pattern. Some of the later heads are so bad [not bad except not easy to increase flow]they even have nicknames. "Lake Tahoe", "Block head", and " Bleeding Heart", etc. Even some of the aftermarket heads are beyond reason. I am not going to mention a company that has a really good head for these motors, but rumors suggest there is a real solution to almost double the HP with the right head.

Have fun,
 
Actually I bought all of them from Whizzer as they removed them for the first NE5s

Very few were ever sold on the bikes, because Whizzer USA pulled them when they realized the restictor could be removed in a few seconds. Removing the restrictor allowed them to easily exceed 45 MPH and Whizzer felt it important to keep the bikes below 30 MPH to meet some states motorbike [moped] rules.


Do I still have some of the original carburetors? Most likely I do, as I have them on almost all the new edition Whizzers in my collection, including the "Wheelie" machine, and the 2005 record of 68 MPH on my 99.


It think it important to suggest you bring the power level of your motor up before you attempt to use the 26 MM carburetor. The reason is basic as the heads used on the very first NE motors were different [Yes I do have several in stock] and adapted well to the larger carburetor, however the later heads have a much more scrambled flow pattern. Some of the later heads are so bad [not bad except not easy to increase flow]they even have nicknames. "Lake Tahoe", "Block head", and " Bleeding Heart", etc. Even some of the aftermarket heads are beyond reason. I am not going to mention a company that has a really good head for these motors, but rumors suggest there is a real solution to almost double the HP with the right head.

Have fun,

I have done quite a few mods to my engine, and plan on doing more. The stock WC1 carb would have definitely not been enough carb for my engine. I'd rather run a little on the rich side vs. the lean side.
 
whizzerpaul has two of those compression release plates WITH the boss cast into it on ebay right now. Price is a little steep, IMO, but at least the parts are still available.

Drilling and tapping will work; I have a backup engine that has a plate done that way.
 
Just drill and tap with pipe threads in the upper left corner, make sure the fitting doesn't contact the edge of the tappet cover boss on the cylinder.

If you make it too small it won't work correctly [needs to be larger than 1/4"].

The stock WC-1 carburetor is approx. 19.7 MM whereas the current carburetors used are only 16 MM [approx 14 mm venturi].

In order to select the correct carburetor size it is important to understand that the "mouth" size isn't the venturi size. As an example the 26 MM Whizzer carburetor has a 22 MM venturi, whereas the 22 MM has a 20.8 MM venturi, and the venturi size on the 19.7 MM is approx. 18 MM. It is also important to know the motor has to have a certain flow in order to LIFT the fuel from the float bowl to the venturi. The valve size and camshaft play a major role in using larger carburetors. Having said all that, how efficient is it to have a larger venturi than the I.D. of the valve seat or valve pocket. As an example the I.D. of the NE intake valve seat is; are ya ready??? 20.8 MM [same size as the 22 MM venturi size]. The WC-1 intake valve seat I.D. is 18.4 MM [very close to the WC-1 carburetor].

Just thought I would mention these items because the trend is to put as big a carburetor as can be connected to make it go faster, when most often it slows down the motor on top end.

While it is true I use the massive 26 MM carburetor on my motors, however the flow of the head and camshaft allow the larger carburetor to work well, unlike a stock head or camshaft.

In order for the larger carburetor to work correctly the head and valve train must be upgraded. As far as I know, only one head ever offered by Whizzer can handle the larger carburetor. The head was on the motors that had the 26 MM carburetor in late 2004 and early 2005 models. The head can be identified by the "island" being removed with a ball end mill. Another head that can be made to work is the "block" head currently offered on motors from Taiwan, however the spark plug must be in the correct hole and the head must be milled .090".

Hopefully I haven't discouraged anyone, but most often the larger carburetor slows down stock motors [just seems faster cause the money was spent].

Another important comment pertains to too rich or too lean. It is almost as bad to run too rich as too lean because the excessive gas washes the oil from the cylinder, rings, and piston causing a lot of serious issues.

hope this helps in selecting the right carburetor size.

Have fun,
 
I'm not new to the world of hot rodding, maybe hot rodding a Whizzer engine, but not engines in general. The principals are typically the same.

As I said, I have done mods to the engine, and plan on doing more. I also did say a LITTLE on the rich side. As a matter of fact, most vehicles are programmed to run a little on the rich side especially when cold, that's why you never smog an engine when it's cold. You don't want detonation which is worse in my opinion.The head I have on my engine is the head I believe you're mentioning with the dual threaded holes one of which is said to be the "compression release" and the other for the spark plug. I have my spark plug in the front hole, not sure if it really makes a performace difference, but I could always try and find out. I had the head milled as well.

As you may know, there is more to determining carb size then just intake valve size. As you mentioned the cam (lift and duration) are an important factor to consider as well as max RPM and engine CC or CI size. For example,using this formula:
Engine size (CID) x maximum RPM / 3456 = CFM
At 100% volumetric efficiency an engine with 302 C.I. that revs to 8,500 RPMs requires at least a 750 CFM carb where as a engine with 400 C.I. that revs to 5,000 RPMs requires only 600 CFM carb. Of course I had to round off on the carb size because they don't make a 578 CFM or 742 CFM carb as far as I know. Again, I like to round a little higher for said reasons which typically the manufactures do as well to avoid dangerous detonation.

I'm not having that backwoods thinking of "bigger is better" in this case.
 
Exactly!

It is the sum of the parts not the size.

The spark plug belongs at the rear, as in the front location it is between the incoming charge and the piston. Also try to index the plug as it makes a major difference on this little flat head.

Head works best if chamber reduced to a reasonable size and compression is raised. The head needs to lose more than any other Whizzer head because of the DEEP chamber. Should take off between .085" and .090" and use .010" copper head gasket for best flow. If using a thicker gasket, deduct the difference from head. Final compression pressure should be from 115 to 125 pounds [using a stock NE late edition camshaft].

Hope this information is helpful
Have fun,
 
Yes, your info is always helpful, you definitely know your Whizzers.

It's going to be raining for the next few days here, so I'll have plenty of time to install a hose nipple on the "valve cover" plate for my breather, adjust the carb, and run the new Iridium spark plug. Indexing is sometimes difficult, I guess I could use washers to get the plug to face exactly where I want it vs. having to try multiple different spark plugs.

I had my head milled only .070". The machinist that did it didn't feel comfortable going farther than that... Sounds like I still have some room for improvement there...

Thanks.
 
If possible aim opening at center of piston, save washers from replaced spark plugs for future use. I normally buy a box and mark them with a marker for future use.

The additional .020" will make a difference and worth doing.

I normally use a 1/4" end mill and deepen the existing fins and add several more in the process. Helps head dissipate heat much better.


Have fun,
 
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